Aromatic polysulfone resins have been noted as engineering plastic for electric parts or automobile parts because of their excellent heat resistance, strength, rigidity, flame retardancy, chemical resistance, etc.
With the recent technical development in these fields of application, it has been demanded to develop a resin material having further improved heat resistance, strength and rigidity while retaining the properties characteristic of the aromatic polysulfone resins, such as flame retardancy, chemical resistance, hot water resistance, molding processability, and the like.
A resin composition comprising an aromatic polysulfone and a potassium titanate fiber has been proposed ad hoc. In this composition, however, as the proportion of a potassium titanate fiber increases to ensure a high reinforcing effect, it undergoes gelation to lose fluidity, making molding impossible while being retained at high temperatures in melt processing, e.g., injection molding.